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Metadata

Author/Creator

Date

2008

Type of Work

7 p.Textjournal articlesresearch articles

Department

Physics

Program

Bachelor's Degree

Rights

Collection may be protected under Title 17 of the U.S. Copyright Law. To obtain information or permission to publish or reproduce, please contact the Goucher Special Collections & Archives at 410-337-6347 or email archives@goucher.edu.

Subjects

Abstract

The ball-milling technique employs mechanical energy to reduce the particle size of reactants to a size
small enough to cause defects in the reactants’ lattice structures and produce active sites. In exothermic
reactions, solid-state diffusions within these active sites induce self-heat propagating synthesis (SHS),
allowing a complete reaction via mechanical energy. However, extracting silicon from silicon oxide using
aluminum is endothermic, and therefore milling alone does not complete the reaction. This study sought to
supplement the solid-state diffusion via the lattice defects with energy supplied by moderate heat treatment
as a method of producing pure silicon and to investigate the parameters of this method to maximize its
efficiency. The parameters tested were annealing temperature, milling time, and annealing time. The
relationship between annealing temperature and milling time was also investigated thoroughly. X-ray
diffraction, as well as some comparison with Atomic Force Microscopy, was used to determine the
presence of products in samples. The data confirmed that milling is necessary for the reaction to take
place, and that even one minute of milling can change the products significantly. The use of milling,
combined with a moderate heat treatment, can produce silicon in a way that is more environmentally
friendly and cost-effective than current methods and can be used at tonnage proportions for industrial
purposes.